Lockdown Lessons Learned During Covid

We are two and a half years into the Covid-19 pandemic. Data has accumulated on the effectiveness of lockdowns in reducing deaths and of the costs associated with lockdowns. The overall effectiveness of lockdowns must consider both aspects. Moreover, lockdowns took different forms in different places—total, targeted, etc.  Dyani Lewis has provided a very careful review of the major studies of these data in Nature  “What Scientist have Learnt from Covid Lockdowns

To overcome issues of correctly attributing deaths to Covid, excess deaths is generally used (excess from all causes each period over the recent—usually five year– average for the same period). “The pre-vaccine period of the pandemic does show that countries that acted harshly and swiftly — the ‘go hard, go fast’ approach — often fared better than those that waited to implement lockdown policies. China’s harsh lockdowns eliminated COVID-19 locally, for a time.” But the economic and public moral costs in China are very large and continue to mount. “The most effective measures were policies banning small gatherings and closing businesses and schools, closely followed by land-border restrictions and national lockdowns. Less-intrusive measures — such as government support for vulnerable populations, and risk-communication strategies — also had an impact. Airport health checks, however, had no discernible benefit….

“The impacts of lockdowns also differed from one pandemic wave to the next. By the time second waves emerged, so much had been learnt about the virus that people’s behaviour was quite different…. These changes dampened the extent to which countries benefited from lockdowns” because people adjusted on their own.

“There’s a fundamental difficulty with analysing the effects of COVID-19 lockdowns: it is hard to know what would have happened in their absence…. [Many studies] could have overstated the size of the benefit because it assumes that without lockdown mandates, people wouldn’t have reduced their social contacts. In reality, rising deaths would probably have changed people’s behaviour….

“And lockdown policies did bring costs. Although they delayed outbreaks, saving lives by allowing countries to hang on for vaccines and drugs, they also brought significant social isolation and associated mental-health problems, rising rates of domestic violence and violence against women, cancelled medical appointments and disruption to education for children and university students. And they were often (although not always) accompanied by economic downturns….

“Pure economic analyses of whether lockdowns were worth it generally try to estimate the value of lives saved and compare that with the costs of economic downturns. But there is no consensus on how to make this comparison…. Not all harms can be [objectively measured]. Loss of education because of school closures might indirectly harm children in the long run, potentially decreasing their future earnings and placing them at greater risk of poorer health outcomes…. Such harms are so far off — decades, in some cases.”

Learning the lessons that experience teaches us is very important when formulating public policy. But extracting those lessons can be difficult. Lewis’s summary is the best I have read, and I urge you to read it. I continue to believe that when we are provided the best understanding available (which obviously grows over time) we will each make the best decisions for ourselves and our families, striking the balance that is best for each of us.